Frank j



@niet-eh tutes' getest @ffice IMPROVEMENT IN PISTON PACKING.

SPECIFICATION- ,f

TO ALL WHOM IT MAY GONCERN:

Be it known that I, FRANK J. ROTH, of Newark, in the` county of Lieking, and State of Ohio, have invented a new and improved Piston Packing; Vand I do hereby declare that the following is a full, clear, and .exact description thereof, reference being had to the accompanying drawings, making a part of this specification, in whichi Figure 1 is a diametrical section through the improved piston packing.

Figure 2 is an end view of the piston, with the follower removed.

Figui-e3 is a central section through the central ring.

Figure 4 isfavicw of the packing-rings and their spring.

Figure 5 is a diametrical section through the central ring.

Figure 6 is a diametrical section through the packing-rings.

Similar letters of reference indicate corresponding parts in the several figures.

This invention relates to certain novel improvements on that class of packing for pistons which is composed of metallic sections, forming, when put together, expansible rings, which are applied within annularrecessesA that are formed in the circumference of the piston, so that when acted upon by the steam, these ring sections` will be forced out against the inner surface of the cylinder, and thereby pack the piston. In this class iof pis.-` tons, the steam is caused to act upon the packing from the inside outward, provision being made for the passage of the steam into chambers formed in the piston, and thence through an outer ring which receives the packing-rings.

The main object of my inventio`n..1, sA to so construct and apply sectional(packing-rings to a pistor'i`,that superior advantages s hall be Vsecured over what have been heretofore experienced in that class of pistons which have their packing expanded by steam acting upon the rings without entering into the piston.

Another object of my invention is to provide, in horizontally working pistons, against an unequal wearing away of the same, by the application of an elastic plate to that part of a pistou which slides upon the lowest` point of the interior of the cylinder, which plate shall compensate for the wear caused by the gravity` of the piston, as will be hereinafter described. i

To enable others skilled in the art to understand my invention, Iwill describe its construction and operation.,

In the accompanying drawings,"A B represent two circular portions which constitute the4 body of the piston, A being the spider, and B its follower, which parts are constructed and bolted together in the usual manner, as shown in the drawings. When these two parts are bolted together, they form an annular space between theirflangesfor the reception of a central ring, C, which is supported by the .ends of the radial arms of portion A, so as to lap over the joint of the two parts, A B, as shown in iig. I, and thus prevent the entrance of steam into the body of the piston.- The ring rC has a central annular ridge which leaves on each side'pf it an annular space for receiving the expansible rings. This centre ring, C, forms two sides for each expansible ring, the other side being formed by the circulaniianges of the piston, as shown in flg.1. The inner corners of the circular iianges of the piston are bevelled, as shown at a a, for receiving the corresponding bevelled surfaces of the packing-rings b b, portions of which rings are fitted loosely but snugly within the annular chambers above described, so that their circnmferences project short distances beyond the circumference of the piston andl ring C. The packing-ringsbb are'made up, of segments or sections, and are held out, so that their outer surfaces press gently against the inner surface of the steam cylinder, by means of springsc c, the ends of which are bent outward, as shown in figs. 2 and 4,so as to act, upon the ends of the segments btb, andthus to keep the ends of all the segments snugly together, except those segments between which the springsare -bent outward. `'.lhese springs c c not only act to expand the sectional packing rings, but they also operate to keep the ends of the sections together, so as to form tight joints. -To prevent the entrance of steam within the chambers occupied by the springs c c, I form recesses in the ends' of those segments which receive the ends of the springs c c, and insert into said recesses `short pieces G, which 4break joints with the jointsof said segments. `The segments G may be riveted to the segments b, on one side of the joint. For horizontally working pistons, where the weight of the piston is supported upon the bottom inner surface of the cylinder, ,It employ a segment g, which is inserted into a recss formed in the ridge of ring C, and acted upon by a spring h, which supports, or nearly supports, the weight of the piston upon said piece, g this piece g may be made of.l brass, Babbit metal, or of any other suitable metal; and as its outer surface wears away, the spring will force it outward, so thatthe anis of the piston and axis of the cylinder withinwhich the piston works, will always coincide. This will prevent the piston and the Shilling-box of its rod from wearing untrue. Where the weight of the piston is supported by the piston-rodLas in upright cylinders, the plate g and spring h may be dispensed with. It Vwill be seen, by reference to g. 1, that the circumference of the packing-rings projects beyond the circumferenceof the pistonilanges; this allows steam to pass these-flanges, and. act upon the projecting bevelled surfaces of the packingrings, andvexpa'nd them against the surface of the cylinder with a pressure` commensurate with the force of steam. The springs c c, which I employ, are designed merely to keep the Apacking-rings expanded, and in -contact withthe innersuri'ace of the cylipder Within'whieh the'piston works, so, that they are always in a. position to be acted upon by the steam and forcibly expanded thereby. I do not conlne my invention to steamengine pistons, as it is applicable .to pistons for air and water engines. The segments 6 may be made rectangular or other suitable shape in cross-sectiomtwithout departing fromthe principle of my invention.

What I claim as new, and desire to secure by Letters Patent, isy '1. The application of expansible packing-rings to the circumference of pistons, in such manner that said rings shallbe expanded by the pressure of steam upon suoli portions of themas are exposed beyond the periphery of the piston, substantially as described.

2. The arrangement of spring plates g to recesses formed in the circumference of' pistons, substantially-as described. i 'i l 3. The arrangement of springs ac, so as to act upon the ends of packing-rings 6 6, which are made up of segments, substantiallyas described.

FRANK J. ROTH. Witnesses:

JOSEPH WM. BURKART, CHARLES ROTH. 

